<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script crossorigin src="https://unpkg.com/react@17/umd/react.development.js"></script>
    <script crossorigin src="https://unpkg.com/react-dom@17/umd/react-dom.development.js"></script>
<!--    用于解析ES6-->
    <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>
    <style>
        .yellow {
            color: yellow;
        }
        .red {
            color:red;
        }
    </style>
</head>
<!--ES6 -->
<body>
    <div id="app"></div>
    <script type="text/babel">
            let hello = React.createElement('h1',{
                className: 'yellow'
            },'hello demo3')
            ReactDOM.render(hello,document.getElementById('app'))
    </script>

    <div id="app1"></div>
    <script type="text/babel">
        let a = 'pp'
        ReactDOM.render(<h1 className="red">hello {a}</h1>,document.getElementById('app1'))
    </script>
</body>
</html>